Liquid feeding device



Aug, 30, 1932. R w DAVY 1,874,249

' LIQUID FEEDING DEVICE Filed Jan. 15, 1951 s Sheets-Sheet 1 gwumtoc vRmhard 1D. Davy,

Aug. 30, 1932. R DAW 1,874,249

LIQUID FEEDING DEVICE Filed J n- 1931 5 Sheets-Sheet 2 Aug. 30, 1932. R.w. DAVY 1,374,249

LIQUID FEEDING DEVICE Filed Jan. 15, 1931 I5 Sheets-Sheet I5 damn,

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Patented Aug. 30, 1932 PATENT OFFICE RICHARD W. DAVY, OF'NEW YORK, N.'Y.

. LIQUID FEEDING DEVICE Application filed January15, 1931.

My invention relates to a fuel feeding device for internal combustionengines by means of which fuel is drawn from a main supply tank usuallylocated below the level of the carburetor, into a storage tank above thecarburetor and delivered by gravity to the carburetor as required.

Heretofore, the better known makes of fuel feeding devices have beensubject to mechanical defects which have seriously affected theoperation of the devices. One of the commonest causes of failure. of thedevices is leakage of the air inlet valve due to the rapidity with whichsaid valve is moved by its operating mechanism. Another difficulty withthese devices is the uncertainty of priming the vacuum tank thereof,should the main fuel tank be emptied and then refilled, as generally,there is sufficient leakage of the valves to prevent the vacuum fromreachmg a value suificient to draw in the fuel, even though the motormake many revolutions. The common practice is to prime either the vacuumtank or the carburetor in order to avoid undue cranking.

" economic viewpoint is the method of manufacturing and assembling thedevice. All the parts of the device may be formed by such simplemechanical operations, as drawing, pressing and punching, since anappreciable variation in dimensions on most of the parts is permissible.

The specific embodiment of the device described herein to illustrate theprinciples of the invention includes a storage tank, a pumping chamberhaving means for automatically controlling the pumping of fuel from amain tank to the pumping chamber and means for controlling the flow offuel from the pumping chamber to the storage tank. Various other objectsand aspectsof Serial No. 509,001.

the invention will become apparent from a perusal of the followingdetailed description thereof, wherein reference is made to theaccompanying drawings, in which:

Fig. 1 is an outline view of a motor car with the device and attendantparts shown thereon.

Fig. 2 is a plan view of the device.

Fig. 3 is an elevational view of the device.

Fig.4 is a sectional view taken along line 4-4: of Fig. 5. i

Fig. 5 is a vertical sectional view of the device with the parts in apumping position.

Fig. 6 is a sectional view taken along line 6-6 of Fi 5, with parts ofthe foot valve broken away.. i

Fig. 7 is an enlarged fragmentary sectional view similar to Fig. 5 withthe parts in a nonpumping position.

Fig. 8 is a sectional view taken on line 8-8 of Fig. 7 looking in thedirection of the arrows. V

Fig. 9 is a fragmentary group perspective showing the cap indisassembled relation to the pumping chamber. 7

Referring to Fig. 1 of the drawings, there is shown in broken lines theoutline of a motor vehicle 10 which includes an internal combustionengine (not shown) havingan intake manifold 11, a carburetor 12, an aircleaner 13 therefor, and a main fuel tank 14 which is at atmosphericpressure. The fuel feeding device 15 connected to the tank 14 by a tube16 and to the carburetor 12 by a tube 17 receives its suction through atube 18 connected into the manifold 11. The entire device 15 may bemounted to the dash, or any suitable place on the vehicle, above theliquid level in both the tank 14 and the carburetor 12 with the distanceabove the lowest liquid level not greater than the height of a liquidcolumn that can be supported by the available source of vacuum. The,device may be mounted to a portion of the vehicle'19 as by a strapbracket 20 and suitable fastenings 21.

The fuel feeding device includes a storage tanker compartment ofsuitable size formed of atubular portion having its upper end fianged asat 26, a flanged closure 27 for said end is detachably secured theretowith an annular gasket 29 interposed between said parts, and a closure31 for the lower end of tank which may be formed integrally therewith.The tubular portion 25 is further formed with circumferential ribs 30which prevent the tank from slipping through its supporting bracket orbrackets. lVhether formed integrally, or as shown, the lower closure 31is formed with a depressed portion 32 which serves as a sediment sump.

An inlet tube 33 projects into the tank a considerable distance, beingsecured in a flanged opening 34 formed in the depressed portion 32 ofthe closure 31 and reinforced by a flanged collar 35. An outlet tube 36projects into the tank a short distance being secured in a flangedopening 37 of the closure 31 and reinforced by a flanged collar 38. Thepurpose of projecting the tubes into the tank will appear later.

In the present form of the device a tubular pumping chamber 40 of lessarea than the storage tank is formed with an offset lower portion 41having openings or valve ports 42 and a skirt or flange portion 43 whichis secured in the depressed portion as by soldering. The offset portion41 provides a serviceablevalve seat for a foot valve 44 which controlsthe flow of fuel from the pumping chamber into the storage tank. Thevalve 44 is shown as formed of a plurality of vegetable parchment ringssurmounted by a metal washer heavy enough to insure positive valveaction, but any thin flexible material which is not affected by the fuelmay be used for the rings. The number of rings is to be determined bythe physical properties of the substance used, however, a single washerof soft pliable material may be used as a valve,

providing its specific gravity int-he fuel is,

suflicient for proper action of the valve. It is also possible to useother valve arrangements between the pumping chamber and the tank as theshowing is merely exemplary of the invention.

The closure 27 is formed with a shallow depressed portion 45 and adownwardly proj ecting collar 46 through which the pumping chamber 40projects. with the pumping chamber permits air to seep between saidparts into the storage tank so that the storage tank is supplied withatmospheric pressure. Besides providing an air vent for the storage tankthe collar also serves as a baflie to prevent loss of fuel by surging orsplashing. Since the liquid is in the form of an annular cylinder anymotion imparted to it by a given movement of the tank is less than ifthe liquid were in the form of a plain cylinder. Such motion of theliquid as does occur, causes it to. flow around both sides of thepumping chamber and pile upat one side of the tank. If it rises highenough to reach the top of the tank, it is The fitof the collar I firstdeflected by the flange 26 then by the collar 46. As an added protectionagainst leakage between the pumping chamber and collar, the depressedportion 45 may be provided with a flexible gasket 47 which closely fitsthe pumping chamber and prevents fuel from going further up the outsideof the pumping chamber. The flexibility of the gasket and the relationof its inner edge to the rounded edge of the depression is such thatshould the pressure in the storage tank fall an appreciable amount,atmospheric pressure will tend to flex the gasket suiliciently to permitair to seep past the gasket until the pressure in the storage tank isrestored.

The upper end of the pumping chamber is formed to receive a valvemechanism 48, a float container or chamber 55, a float 60 operativelymounted therein for actuating the valve mechanism, and a suctionconnection 76. In the present form of the device the valve mechanism 48includes a closure plate 49 for the pumping chamber detachably securedto a flanged portion 50 of said chamber by screws 51. The closure plate49 is formed with a cup-shapedportion 52 having an atmospheric port 53at the lowest part thereof. The port is formed with a valve seat inwhich a ball valve 54 is normally seated by gravity. The float container55 in the form of a tube of less cross-sectional area than the pumpingchamber and, having the lower end 56 closed, is formed with an inwardlyflanged enlarged upper portion 57 which is press fitted into the upperend of the pumping chamber 40 and is further supported as by the screws51. Near the top and below the enlarged portion 57 of the floatcontainer 55 fuel inlet ports 58 are formed. Adjacent the end 56 of saidcontainer ports 59 are formed.

A float 60, preferably formed of copper to lessen the tendency towardsfatigue and eventual failure as a result of flexing due to changes inpressure inside and outside of the float, is formed as with a tubularbody 60 having separate top and bottom caps 61 and 62. The caps 61 and62 are formed with external flanges 63 and 64 respectively which centerand guide the float in the float container and prevent the thin metalwalls the body 60 from rubbing against the container. The upper flange63 being blank also serves as a baffle to prevent fuel from surging orsplashing thereabove and getting into the vacuum connection. The top cap61 is provided with a s1 .all cross hatched disc 65 which contacts withthe ball valve 54 when the float is raised, preventing the The lowerflange 64 should be perforated or serrated to permit maximum circulationof fuel past the flange without reducing its effective outside diameter(see Fig. 8).

Displacement of the ball valve 54 from the cup-shaped portion 52accidentally or due to road shocks, is prevented by a cap 7 0 which hasa depressed portion 71 so positioned with respect to the cup-shapedportion that the space between said portions 52 and 71 is less than thediameter of the ball valve. In the present form of the device the cap isformed with an external flange 72 and an inverted L-shaped slot 73 theshort leg of which is provided with a notch 74. The slot 73 issufficiently wide at all points so the cap may be attached and detachedfrom the device without disturbing the vacuum connection 7 In attachingthe cap to the device the slot is positioned opposite'the vacuumconnection 76 and the cap moved downwardly until the flange 72 rests onthe gasket 47. in this position the bottom of the short leg of the slotwill be too high to pass under the vacuum connection 7 6 so the cap musthe forced downwardly until said portion of the short leg is aligned withthe bottom of the connection. Forcing the cap downwardly causes aflexing in the closure 27 so that when the cap is turned until the endof the short slot contacts with the vacuum connection 76 and the forceis removed, the residual spring in closure 27 will cause the notch 74 toengage the vacuum connection and retain the affected parts in leak-proofrelation. The slot '2 3 will admit air into the space between the capand the pumping chamber and as before described into the storage tank.In order to prevent anyforeign matter entering the tank an air cleaneris provided as b securing a porous pad or fine mesh screen 75 ofsuitable size to the pumping chan'iber so that it will completely screenthe slot 73 when the cap is in position. The vacuum connection 7 6 isprovided with a restricted portion 77 for a purpose to be hereinafterdescribed. Or, as indicated in broken lines in 1, a tube 78 may beconnected to the carburetor intake back of the air cleaner 13 and to thecap 70 so that a supply of clean air will be available to maintainatmospheric pressure in the storge tank.

In practice it has been found that certain dimensional relations betweenthe parts should be maintained to obtain a' iven resuit. For example,the area'of the annular space between the pumping chamber 40 and thefloat container 55 shouldbe equal to, or greater than, the crosssectional area of the inside of the inlet tube 33. The total area of theports 58 in the float container 55 should be greater than either of theaforementioned areas. The combined area representing the space betwe nthe float and float container and the openings 59 in the float containershould also at least be equal to the efiective area of the inlet tube33. A smaller area between the pumping chamber and the float containerwould cause restriction of liquid flow and consequent delay in operationof the device. 7 A smaller area between the float and float containerwould result in a portion of the liquid entering the ioat containerbeing drawn into the vacuum connection by the suction thus disturbingoperation of themotor.

The diameter of the ball valve 54 and the size of the float 60 areinterdependent and are governed by mechanical conditions necessary tothe proper operation of the device. The

size of the valve port 53 should be'such that not less than two thirdsnor more than three quarters of the radius of the ball will pro jectbelow the lower edge of the port. An increase in the diameter of theball to give a larger valve port would necessitate, a larger float, alarger float container and a larger pumping chamber which in .turn wouldreduce the capacity of the storage tank. A smaller ball, to giveincreased capacity without too large a storage tank, would not onlynecessitate a smaller valve port,but, dueto the decreased radius of theball would decrease the height to which the ball could be lifted fromits seat.

A primary factor in the control ofthe period of the cycle is the size ofthe ports 59 at the base of the float container. Their dimensions shouldbe such that the interval of time between the lifting and reseating ofthe ball valve is approximately the same as the time required for thetransfer of a maximum quantity of fuel from the pumping chamber to thestorage tank when said tank is initially empty, or nearly so. An errorin this dimension, however, will have no other effect in the operationof the device than to decrease the pumping capacity. Y The fuel inlettube 33 should be extended well up into the pumping chamber, as close aspractical to the bottom of the float container; This is to safeguardagainst the storage tank draining itself back into the main fuel supplytank should the foot valve prove to be not absolutely tight. Of thevolume of liquid 'in the pumping chamber above the fuel inlet tube, acertain amount drains back down the tube at each cycle. This quantity issmall, however, since the volume of the fuel above the top of the tubeis small in comparison to the volume below the tube and since the crosssectional area of the inlet tube is small in comparison to the totalarea of the ports 42 of the foot valve. 7 i

- The fuel outlet tube 36 should be extended a short distance above thebottom of the storage tank to provide a sump in which sediment may becaught and prevented from passing into the carburetor supply line 17 andto provide a liquid seal for the foot valve; In the tighter againsttheir seats.

event that the main fuel supply tank is exhausted and the storage tankis drained to the level of the outlet tube 36, the device may be made tofunction by simply filling the main supply tank and turning the motorover a few times with the throttle closed. If the liquid seal were notmaintained, a bit of sediment on the valve seat might permit air toenter the pumping chamber as fast as it could be removed through thevacuum connection, thus rendering the device inoperative.

Operation With the device connected to the main fuel supply tank 14 andto the carburetor 12 and the intake manifold 11 substantially as shownin' Fig. 1 the device is ready to begin its cycle of operations. At thistime the foot valve 441- will be closed, the float 60 will be resting onthe bottom of the float container thereby permiting the ball valve 54 toseat itself. As the motor turns over a vacuum will be formed in thepumping chamber and will tend to pull the foot valve and the ball valveSaid vacuum also tends to draw fuel from the main supply tank 14 intothe pumping chamber 40. by way of the inlet tube 33. hen the liquidlevel of the fuel being drawn into the pumping chamber reaches the ports59 in the bottom of the float container. a portion of the fuel will runthrough these openings tending to fill the container. Since the area ofthese ports is small in comparison to the area of the inlet tube andsince the volumes to be filled inside and outside the float containerare approximately the same, the liquid level of the fuel outside thefloat container will rise much quicker than the liquid level inside saidcontainer until the ports 58 in the container are reached. The totalarea of said ports being greater than the annular space between thepumping chamber and the fuel inlet tube 33 permits all the fuel risingaround the container to flow through the ports into the container untilthe buoyancy of the float is suflicient to lift the ball valve from itsseat. For the float to function, its buoyancy must exceed the weight ofthe ball, plus the force of the vacuum in the pumping chamber tending tokeep the ball valve seated. Once the force of the vacuum is overcome theentire upward force of the float is exerted against the weight of theball alone, as the air pressure on all surfaces of the ball becomessubstantially equalized due to the air rushing in. This results in aprompt positive valve action. The float and ball continue to rise as aunit until the top of the float comes in contact with the under side ofthe valve seat. In this position by virtue of the cross hatched disc 65practically all of the area of the valve opening is available to thefree passage of air into the pumping chamber. Then, since the area ofthe vacuum connection 76, due tothe restriction 77, is less than thearea of the valve port the pressure inside the pumping chamber willrapidly approach atmospheric. During this period, as the fuel rises inthe pumping chamber, it will exert an increasing force, tending to liftthe foot valve let from its seat, proportional to the increasing head ofliquid in the pumping chamber. The forces tending to keep the foot valveclosed are the weight of said valve plus the difference in pressures onopposite sides of the valve applied over the total area of the ports 42.As long as fuel is being drawn into the pumping chamber this differencein pressures will be at least equivalent to a liquid head represented bythe difference between the liquid levels in the pumping chamber and inthe storage tank 25. Therefore, the foot valve 44 cannot rise from itsseat as long as fuel is being drawn into the pumping chamber.

As before noted, when the ball valve is lifted from its seat thepressure inside the pumping chamber becomes substantially atmospheric,leaving the Weightof the foot valve a l as the only force tending tokeep the foot valve closed when the storage tank is empty. Against thisis the opposed head of fuel in the pumping chamber which lifts theflapper from its seat and permits fuel to flow 1:1

into the storage tank until the levels inside and outside the pumpingchamber are equalized. Theoretically it might be supposed that theliquid level inside the pumping chamber would remain at all times higherthan that outside the chamber by a liquid head equivalent to the weightof the foot valve. In practice, however, this does not hold, due to thefact that the flapper is raised an appreciable. distance above its seatby the flow of fuel against its lower surface and at the theoreticaltime when the valve should reseat itself, it is still in the processv ofsettling down against the liquid flow. Therefore the two liquid levelsof the fuel in the storage tank if and the pumping chamber become verynearly equalized before the foot valve is finally closed.

When the liquid level in the pumping chamber begins to fall, fuel willbegin to drain from the float container through the ports 59. As theliquid level in the float container falls, the effective buoyancy of thefloat will gradually decrease until equalled by the weight of the ballvalve. The float and ball valve wil then descend as a unit at the samerate as the lowering liquid level until the ball is seated, therebycompleting the cycle of operations.

As the fuel rises in the storage tank, the

amount transferred from the pumping chamlfli , ing of the upper closure.

fuel in the storage tank due to the requirements of the motor isautomatically compensated for until the liquid flow is in equilibrium.

It should be noted that there are only three moving parts which at notime during the operation of the device rest on other parts in relationto which they are moving.

What is claimed is:

l. A liquid fuel feeding device comprising a vacuum actuated fuelpumping means, a fuel storage tank in communication therewith, and alower and'an upper closure for the tank, said lower closure formed witha depressed portion which rigidly receives the pumping means andprovides a sediment sump, said upper closure formed with a depressedportion having an opening through which the pumping means freely extendswhereby air is admitted to the storage tank and any fuel passing fromthe tank to the depressed portion is containedtherein until it drainsback into the tank.

2. A fuel feeding device comprising a storage tank having a lower and anupper closure,

a suction actuated pumping means rigidly mounted in said lower closureand extending through an opening in said upper closure with an air-leakfit for the admission of air to the tank, and a detachable cap securedwith the pumping means and acting to hold the upper closure operative,said cap having an opening for the admission of air to the open- 3. Afuel feed comprising a pumping chamber having a. fuel inlet and a valvecontrolled fuel outlet, a float compartment'having an unvalved primaryfuel inlet at the 1,, bottom thereof and a secondary inlet port at anupper portion thereof, an atmospheric vent for the compartment, a valvefor the vent, a float arranged in the compartment to rise with the fuellevel therein to unseat the valve, and a suction port for thecompartment, said primary inlet being of less area than the fuel inletwhereby the fuel outside the compartment will rise more quickly thanthat inside the compartment, said secondary port being of relativelylarge area to permit unrestricted inflow of fuel into the com- Gilpartment when the outside fuel level reaches said secondary portswhereby the float will quickly respond and unseat the valve.

l. In a fuel feed apparatus, a storage tank having a removable closure,an inlet compartment arranged within the tank and projecting through'theremovable closure, a suction pipe connected to the projecting portion ofthe compartment, means within the compartment for controlling theadmission of liquid fuel thereinto, said compartment having valvedcommunication with the tank, and a cap receiving the projected, portionof the compartment and seating on the closure to secure the latteragainst unauthorized displacement, said cap having a slot receiving thesuction pipe and interlocking therewith to secure the cap theretoagainst accidental displacement, f .7 v .-.1 T .i

' 5. In a liquid fuel feeding device, a storage tank open at its top, aninlet compartment secured tothe base of the tank arranged thereimsaidcompartment extending through the open top of the tank, a removableclosure forthe tank throughwhich the compartment projects," saidcompartment having valved communication with the tank adjacent its lowerportion, said tank having an outlet, an li'llGi) for the compartment,means within the compartment for lifting fuel thereinto, and a capenclosing the upper end of the compartment and removably interlockingtherewith,

said cap engaged with the closure for securing the same in position.

6. In a liquid supply device, suction actu- 'ated pumpingmeans includinga tubular a storage tank communicating with casing, the pumping meansthrough a liquid outlet portin the latter, said tank having a closureportion with an opening receiving said tubular casing with an airdeakfit, said closure portion having a depending flange defining saidopening and constituting bafiie means to direct any splashed liquid inthe storage tank downwardly and away from the air-leak fitted portions.V 7. In a liquid supply device, suction actuated pumping means includinga substantially closed tubular-casing having a valved air inlet port andhaving a fuel outlet port adjacent the bottom thereof, a storage tankdisposed about said casing and communicating with said outlet port, adetachable closure for said tank having an opening receiving the casingwith an air-leak fit, and a cap having an air vent secured over saiddetachable closure and tubular casing.

8. In a liquid supply device, pumping means including a tubular casinghaving a peripheral enlargement at its lower end, a storage tankdisposed about said casing and enlargement and having a fluid dischargeopening above the level of said enlargement,

said enlargement having a fluid port therein, and an annular valveextending about the tubular casing and guided thereby, said valve beingin the storage tank and normally closing said fluid port.

9. In a. liquid supply device, pumping means including a pumpingchamber, a storage chamber,said pumping chamber having a tubular partprovided with a port discharging upwardly into said storage chamber, anda valve in said storage chamber normally seating over said port, saidvalve engaging said tubular part for being guided thereby between seatedand unseated positions.

10. In a liquidsupply device, a float con- ,tainer, a closure thereforhaving an inclined depressed central portion providedwith a central airinlet opening,'a ball valve seated in'said opening, said valve beingguided to its-seat by the inclined depressed portion, a float in saidcontainer having undulations thereon for engagement with the ball valvewhen the fioatis raised, the space between I said undulations providingair passages between said inlet opening and the container interior.

RICHARD W. DAVY.

